The present invention relates to animal and poultry husbandry apparatus and systems, and, more particularly, poultry nesting systems having removable nest pads.
A wide variety of apparatus have previously been used for raising poultry and other animals. Using the poultry husbandry technology as the exemplary format in this discussion, it has been suggested to raise egg laying hens, breeder birds and other birds within poultry houses or barns by means of numerous rows of cages or partially enclosed nests for individual birds. Previously, wood shavings, straw and other particulate matter have been placed in the bottom of these nests to simulate the grass of a natural nest and offer some degree of protection for the bird and eggs against abrasion and damage. However, such materials have not been sufficiently sanitary and have required frequent replacement. To minimize the time and effort in replacement and to maintain more sanitary conditions for the poultry and the eggs, artificial nest pads have been used in place of particulate matter.
Various different types of artificial nest pads have been used. In general, these pads were formed from deformable or resilient plastic material and had a planar configuration with a plurality of closely spaced projections on the upper surface of the nest pad base, the surface the bird would be in contact with while roosting in the nest. These nest pads were dimensioned so as to closely fit within the nest enclosure and were also often flexible so as to conform to the configuration of the nest floor. In some pads the projections were blunt or round ended soft, rubber cones. In other pads the projections were irregularly oriented, flexible tabs, such as is found in Astro-turf(copyright). In yet other pads the projections were a regular array of flexible tabs arranged in a matrix of tufts. Many pad designs also included flow-through vents, perforations, spacings or holes between some or all of the projections and/or the nest pad base to allow some or all of the debris, manure or moisture to fall through the pad and out of the nest toward an open area below it, as well as to permit air circulation into the nest. U.S. Pat. No. 5,159,896 shows one example of prior nest pads.
The nest pads were typically mounted within the nest enclosure on an opened surface support structure, such as a perforated web or wire grid, grill or mesh, forming the nest floor. The openings in the support structure provided greater ventilation, ease of cleaning, and reduced fabrication costs. The support structure was not always flat or horizontally disposed within the nest enclosure. Rather, the support structure typically curved from side to side within the nest enclosure and/or inclined from front to back or from side to side. Such non-horizontal orientations were used, for example, to facilitate the automatic removal of eggs from the nest by encouraging them to gently roll toward an exit from the nest and toward a removal conveyor, often disposed adjacent the nest enclosure. The nest pads have previously been mounted on the support structure so as to closely conform to the orientation of the support structure.
However, prior nest pads were not usually permanently mounted to the support structure since, over time, even with flow-through perforations the nest pads became dirty and required cleaning. In general, it has been far easier to reliably clean the nest enclosure and nest pads if the nest pads are removable from the nest enclosure. U.S. Pat. 5,551,460 describes cleaning processes for such nest pads, once removed from the nest enclosure. To some extent, the interior configuration of the nest enclosure does restrict movement of the nest pads within the enclosure and out of it. Unfortunately, the constant movement of the birds into, out of and within the nest enclosure tends to displace the nest pad from its preferred orientation. Over time, the nest pad can even be dragged out of the nest enclosure and onto the poultry house floor or slide into the nest exit intended for eggs, thus clogging the egg removal conveyor.
It has been suggested to form a plurality of vertical, cylindrical projections from the lower surface of the nest pad to restrict migration of the nest pad from the support structure. In order to obtain the desired degree of retention security, such prior projections have had to be formed with relatively large dimensions, projecting further vertically and being thicker in cross-section. Doing so, however, made the packaging and shipping of the nest pads more costly since fewer nest pads could be stacked within a given container without having the downward projections of one nest pad crush or be crushed by the upward projections of the adjacent nest pad. Moreover, the larger projection dimensions increased the likelihood that one or more projections would not fully register with a support surface opening and pass through it, thus preventing the nest pad from properly seating within the nest enclosure. Further, with certain types of nest pads creating a select number of such projections could require prohibitively expensive tooling since the projections extending below the nest pad toward the support structure would typically be diverse in nature, typically more rigid, from the upward projections supporting the bird. Finally, while such vertical projections could, when properly seated, restrict sliding of the nest pad relative to the support surface, they were not positively locked to the support surface, at best providing an slidable, interference fit. Thus, they were susceptible to upward force dragging, for example, if a bird""s claw snagged and lifted the nest pad vertically, and had difficulty in maintaining full seating on curved support surfaces.
Accordingly, it is an object of this invention to provide an improved nest pad for poultry and animals and an improved arrangement for using such nest pads. Further objects include the provision of a nest pad that is:
a. positively locatable with respect to its support structure,
b. easy to install and remove from the nest enclosure,
c. economical to manufacture and market,
d. closely conformable to the support structure configuration,
e. biased against unintended unseating from the support structure,
f. adaptable to a variety of different support structures and configurations,
g. of compact dimension with minimal extension below the pad base, and
h. stackable for shipping, storage, packaging or handling without causing significant deformation of the bird supporting projections on the top surface of each nest pad.
These and other objects of the present invention are obtained through the provision of a nest pad having a plurality of inclined projections extending from its lower surface to register with openings in the support surface and removably engage a portion of the support surface via clamping fit. The inclined projections are arranged in at least two sets, and the direction of inclination of the projections of each such set is opposing and outwardly directed.
Other objects, advantages and novel features of the present invention will be readily apparent to those skilled in the art from the following drawings and detailed description of preferred embodiments.